I finally changed to XT after many years with Vodafone. I have an iPhone 4 and have had increasing problems with Voda in the main cities, although their 900 MHz network works well. Our son changed to Skinny 2 weeks ago and is really pleased with the improved coverage and battery life on his iPhone 3GS.
Well, XT is so much better. For a start, it works well at home where we've always had problems with 2G and 3G coverage. The only phone that ever worked properly was a Nokia E71 with GSM disabled.
I get 4-5 bars of signal everywhere I've been in Auckland so far. Data is much better - no waiting for ages for my email to update. Texts get sent almost instantly.
So a very happy customer so far. I'll be visiting a client tomorrow where Voda coverage is almost non-existent so will be interesting to see if XT is better there.